Surveying instrument



Aug. 31, 1925. 1,598,519

A. D. HADSEL.

SURVEYING INSTRUMENT Filed Sept. 19, 1923 2 'Sheets-Sheet 1 /NVE/VTORAlvi# MMM.' @www 0 A TTORNEYS A. D. HADsEl.

SURVEYING INSTRUMENT 2 Sheets-Sheet 2 Filed Sept. 19, 1923 INVENTOR. //aMdref. BY

ATToRNYs Aug. 31, 1926.

l m C 1 Patented Aug. 3l, 1926.

UNET@ STTS ALVAI-I D. HADSEL, 0F SAN FRANCISCO,

CALIFORNA., ASSGNOR 0F ONE-HALF TO FREDERICK N. WOODS, JR., OF SANFBANCSCO, CALFORNIA.

SURVEYING INSTRUMENT.

Application filed September My invention relates principally to a systemof stadia surveying and graphic plotting, and has for its objectscertain improvements over the apparatus shown and described in myearlier Patent No. 1,428,028 issued September 5, '1922. Amongst theimprovements effected are: a binocular instrument of greater precision,and longer range; no exposed yor movable stadia hairs; larger or smallerscale drawing with same length of instruments, and other features.

These objects are secured in the apparatus shown in the drawings and inwhich:

Figure l is a side elevation of my instrument proper but with telescopesomitted and in place on a plane table;

Figure 2 is a plan view of Figure l omittinp the table;

ligure 3 is an elevation yof the front end of the instrument as seen inFigure l, and Figure 4L the rear end;

Figure 5 is a representation of a telescope of which two are used in theinstrument;

Figure 6 is an lenlarged side view detail r of one `of the straight edgeslides, Figure 7 being a front View of same;

Figure 8 is an enlarged detail of the spring clamps for holding straightedges and telescopes to the pedestal of the instrument;

Figure 9 is a front view of the special stadia rod used with myinstrument or system;

In taking up the detailed construction `of my instrument, the theory ofits use and principle of its projecting the graphic representation tothe plane table need not be gone into as this was discussed in my formerpatent mentioned and is the same for this instrument except as notedhereinafter.

The chief diiference in this over my former instrument is, that insteadof providing one fixed peep hole rand a pair of spaced andlongitudinally movable stadia wires, I provide two complete telescopespivotally arranged side by side, one for the use of each eye, each witha. fixed and centralized transverse hair and `one of the telescopeshaving also a vertical cross hair, the vertical hair being in thetelescope forming the center of the system. These hairs are within Vthein instruments at the objective focal points as usually placed insurveyors telescopes', and the telescopes while parallel as projectedupon a horizontal plane, -are pointing one up and one down at a Slightdivergence fori9, 1923. serial No. 663,710. e

ward, so that they separately sight along the paths `of the upper andlower hairs respectively of my former device mentioned, though the hairsthemselves at the former location are dispensed with, and in theirposition is placed a pair of sliding blocks acting on the respectivetelescope axes for varying the divergence of the telescopes for aligningthe stadia rod targets.

In Figure l the plane table is indicated at (l) and pivoted at (2) to aplate (2) set therein in a pedestal (3). The pedestal supports at itsupper end two parallel metal straight edges (4)--(4:), projectingforwardly. rFliese straight edges are tapering blades placed on edge andhavingv enlarged rear ends (5) provi-ded with screw adjusting yokes (6)at the outer sides of the blades into which a pair yof telescopes isadapted to be clamped, one on each blade. rlhe telescopes are adjustableby means of the yoke screws to optically aline with their respectivestraight edges, also laterally to suit the eye separation of the user.The pedestal has a transverse bore in its upper hub in verticalalinement with the pivot (2) and each blade has secured to it alaterally projecting tubular trunnion (7)-(7), one fittingy within theother and the outer one within the bore so that they may be movedindependently in vertical arcs, side by side, and the telescopes whensecured within the yokes will partake 1of the movement.

To hold the blades tightly against the sides (8) of the hub of thepedestal a spring clamp (9) is snapped over the outsides of the twoblades, projecting between them and the telescope bodies.` The clamppreferably has small tit-s (10) to center in small holes (10) in thepivotal center of each blade so it will not fall off.

f Figure 8 shows the clamp removed from the blades and its constructionwill be readily understood, a wire spring (1l) serving te draw the sidestogether. The construction of the clamp is unimportant as any meanswhich will resiliently hold the blades to the hub ends will suiiice.

The telescopes which attach to the blades are as shown in Figure 5, at(l2), having preferably terrestrial lens systems and with fixedcentralized horizontal stadia hairs at' the focall points as indicatedat (13) in Fig. 4. One of the telescopes has also a vertical hair sothat when the telescopes are mounted `o`n 'the blades, the hairs talrethe positions indicated at. (13) in Figure Je, thc crossed hairs. itwill be observed, beingin the telescope over the pivot (2) with thevertical hair in alinement therewith.

llxtendinglj from the lower part` or the pedestal is an arm (14;)carrying` at its outer end a slidingl carriage (15\ having` an upright(16). The carriage carrying` the upright is movable along the arm bymeans or the rack and pinion indicated at (17)I so that it may beadjusted back `and tortb up'on the arm, and the arm only, or block only,or both may rest upon the table as shown.

The u`pright`(16) is integral With the carriage (15) or firmly securedthereto, and is prvided with a vertically sliding head (18) which may beadjusted up and down 4by the rack and pinion indicated at (19). On bothsides or the sliding head are arranged truu n'ion "bloeks (20), slidablysupporting, respectively, the free ends of the straight edges (et), (fl)Vso that when the carriage (15) is adjusted along` the arm (141-) thestraight edges -ivill slide alongthe blocks 'and when the head (16) israised or depressed the tr'unnions will swivel vto hold lthe straightedges in Contact with their sliding surface.

As shown in Figures 6 and 7 each block (20)'has on opposite 'facesthereof Atrunnions (21) which are revolvably supported bythe upright(1G) and each trun'nion isslotted at (22) to slidab'ly receive one orthe straight edges. The slots in the trunnion bloclrs extend exactly Ytothe Center of the trunnion pivots (21) and the tivo blocks arevertically in line and spaced one above the other a definite distance inrelation to the scale ot graphic plot to be made. this separationhavingl the 'function of the spaced stadia h'airs in the instrumentdescribed in my former patent mentioned.

The sliding;` surfaces ot the straight edges which slide in the blocksare cach in line with the longitudinal axis oli the telescope which itsupports, so that in effect the telescopes bear on their optical axesupon the blocks, and since the axes are supported at an outwardlydiverging angle any adjustment of the carriage (15) along the arm (14)changes the angle 'of the axes.

Vertically beneath the trunnion blocks and in line with the opticalcenter or 'the near or cross hair telescope is the plot indicating'center (23). This may be a pointer bearingv on the plane 'table asindicated in Figure 2 or' the drawing.

The instrument turns on the table around the .pivot (2), and the arm(14) has lpreferably a 'stabilizii'ig pad at its outer end as showninFigure 2 Vat (27). y

The height of 'the linstrument is considered the centeror the transversepiiot (10) about which 'the s'trai-Cfht edges 'swing 'and at which pointthe longitudinal axes of the telescopes meet or cross.

0n the upright (16) is a scale of elevation (28) against which moves apointer (29) on the sliding' head This scale of elevation is preferablygraduated in reet trom a Zero point each Way, thus giving a directreading in 'leet at all points or the plot, the Zero being` taken whenthe center of the projected ang-le or the telescopes (the point midivaybetween the trunnion axes) is level with the `center (10) or theinstrument, though any other point may be taken as Zero. or the upper orlower side or the vangle it desired.

li lthe 'center of the angle is chosen 1 arrange my stadia rod (30) asshown in Figure 9f\vitl1 tivo targets (31), both adjustable array y'froma common center to any desired points A? B or C for changing the scalerelation of the plot. To maintain the height from center to end or vrodvequal to the height of 'the instrument I provide an extensible lowerend (341) clamped by the screw In operation the plane table `is pre1-erab'ly ysecured as shoiv-n in Figure 1() to the top of a revolving headtripod (36) having graduated circle as indicated at (37) so tbz-1t theangula r positions or' the various plottings may be read, though inmaking` the plot on the table the instrument only is turned on the tableon its pivot. to bring the vertical 'hair centered over the verticalcenter of the rod; then with an eye at both telescopes the observerrocks the sliding lage back and forth o'r changes 'the elevation cit'the 'sliding head until the horizontal hairs bisect, respectively, theupper and louer targets7 at which time the indieatingr center V(23)denotes the correa-t position on the plot and the vertical scale (28)the 'correct elevation.

-Having thus described my instrument and outlined its improvements overmy former device, it ivill be seen that `i`vhile 1 described a binocularinstrument ei'nploying complete telescopes, it might be vmentioned thattelescopes may be used Vivi'th or Without a lens system by 'simply-ll'ee'ping` the stadia hairs as rar from the eye as possible.

I claim:

1. 1n a surveying instrument of the char- 'ac-ter described, a tramerotatable about a fixed vertical axis, spaced uprights on said rrame,v apair of telescopes, means mounting said telescopes on common horizontalaxis on one upright, said vmeans projecting rorivardly toward the otherupright, and means on the latter upright engaging said Asupporting.means for raising and lowering the projecting ends :or the telescopes.Y y

e. la s surveying instrument of the charser@ restated, fr at wearableabout a sgr-d vertice axis, spaced 'uprigirts dii eine lee frame, a pairof telescopes, means mounting said telescopes on a common horizontalaXis on one upright, means on the latter upright enga-ging said mountingmeans for raising and lowering the projecting ends of the telescope7said mounting means including straight edges to Which the saidtelescopes are respectively secured, said straight edges being axiallyalined with the telescope and disposed in spaced relation upon thesupportv 3. In a surveying instrumentof the character described, a framerotatable about a fixed vertical axis, an upright disposed at one endportion of the frame, a second upright slidably connected to the frame,means for adjusting the slidable upright toward and away from the firstnamed upright, a pair of telescopes, means mounting said telescopes on acommon horizontal axis on the lirst named upright, said means includingstraight edges extending to the slidable upright, and means on theslida-ble upright for operating the straight edges to raise and lowerthe telescopes.

ALVAH D. HADSEL.

